1. Field of the Invention
The present invention relates to a line printer that is provided with a plurality of printing heads, disposed across a printing range.
2. Description of the Related Art
In inkjet-type line printers, ink droplets are sprayed from nozzles of print heads that are disposed in essentially a single line in a direction that is perpendicular to the direction of feeding of printer paper as the printer paper is being fed, to adhere to the printer to print text and graphics.
In line printers, in a thermal printer, for example, typically a printer head is formed with a plurality of print heads disposed in a line. The use of a plurality of print heads in this way is to improve the yields of the printer heads that are manufactured by being cut out of disk-shaped silicon substrates. A line printer that is structured in this way is a known technology described in, for example, Japanese Unexamined Patent Application Publication 2001-71495.
In a line printer that is structured by disposing a plurality of print heads in a line, as described above, the diameter of a single dot is extremely small when printing with high image quality. For example, when printing at 600 dpi, the diameter of a single dot is about 40 μm. Given this, a shift of the placement position of the print head from the proper position, even if minute, will cause a degradation in the printing quality. Securing this type of extremely high precision positioning, is extremely difficult in practice, and thus a degradation of printing quality due to positional shift of the print head is a problem inherent to this type of line printer.